Apache NetBeans
A powerful editor and graphical debugger for code written in Scilab
Kile is a feature-rich LaTeX editor
Web IDE in single HTML file
A syntax highlighting, code folding text component written in Swing
A lightweight programming environment for Java
Vim-like editing in Eclipse
Turn gVim into a Crestron SIMPL+ IDE.
PHP Support for GNU Emacs
Graph algorithms interpreter, IDE, debugger, 3D visualizations.
JetBrains Meta programming System